At the park north of Goldenrod City. It is held every Tuesday, Thursday, and Saturday.
You don't need a code or anything. Just show up with the pokemon you want to use in the contest as your first in party, talk to the dude in the gateway, and get bug catching!
It would be held in the National Park at Saturdays and Thursdays. You know that tunnel south of the National Park? (Where in SoulSilver and HeartGold there would be a Pokelathon.) There will be a guy next to the entrance and he'll ask if you want to perform. Only one of your Pokemon can go with you.
One of the staple events from Gold & Silvermakes a return in HeartGold & SoulSilver.
It is held at the national park
in the bug catching contest
win first place in the bug catching contest
Win 1st place in the bug catching contest.
only once a day on tuesday thursday and sunday
TM54...or catch a scyther during bug catching contest and he will eventually learn it
Excluding via trading, winning the first prize in Bug Catching contest is the only way to get a Sun Stone in Gold, Silver and Crystal.
Evolve using a sun stone where you can get if you win first prize in the bug catching contest
somewhere
There on Tusday and Wendsday.
Go to the national, and win the Bug catching contest. Only on certain days the bug catching contest will be there.
Bug catching contest
You get it in the Bug Catching Contest